The present invention relates to a powder container for supplying coating powder to a spray coating system.
The powder container according to the invention is in particular suitable for the powder supply of a powder coating system used to electrostatically spray coat powder onto objects in which fresh coating powder (hereinafter also called “fresh powder”) and, as applicable, reclaimed powder (hereinafter also called “recovered powder”) is situated in the powder container and is supplied by a powder-dispensing device in the form of, for example, an injector, a powder pump or a spraying mechanism, in particular a spray gun. The spraying mechanism can be for example a manual spray gun or an automatic gun.
Fresh powder is supplied to the powder container as needed via a fresh powder line from a supplier's container in which the powder supplier supplies the fresh powder to the powder user.
The powder forms a compact mass inside the supplier's container. By contrast, the coating powder should be in a fluidized state in the powder container so that it can for example be drawn out by the suction power of an injector or by means of a dense phase pump and supplied to the spraying mechanism in a flow of compressed air. The powder container thus serves as a powder chamber for storing coating powder, whereby the coating powder in the powder container is normally fluidized so that it can be easily conveyed pneumatically, either to another powder container or to a powder spraying mechanism. As indicated above, the latter can be a manual or an automatic powder spraying mechanism which can comprise, for example, a spray nozzle or a rotary atomizer.
The invention is therefore based on the problem of powder coating systems and associated powder containers needing to be thoroughly cleaned when changing powder (changing from one type of powder to another type of powder), in particular when changing color (changing from a powder of a first color to a powder of a second color), since even just a few powder particles of the previous powder type can result in coating defects when coating with the new powder type.
One task to therefore be solved by the invention is that of providing a possibility for easily changing powder as quickly as possible.